Scientists have resurrected a long-extinct virus closely related to smallpox, and all it took was $100,000 and some mail-ordered chunks of DNA. The research, reported as news in the journal Science, could provide a road map to reconstructing the genome for one of the deadliest viruses the world has ever seen. And some scientists fear the information could help terrorists create dangerous biological weapons.

The resurrected virus is called horsepox, and it could be used to create new, safer smallpox vaccines and virus-based cancer treatments, according to David Evans, a microbiologist and immunologist at the University of Alberta in Canada, who led the research. Horsepox is not dangerous to people, but it is closely related to smallpox, which killed millions before a worldwide vaccination effort eradicated the disease in 1980. So the road map to piecing together the horsepox virus could also lead to re-creating the smallpox virus as well — and that’s controversial.

Evans’ work was first discussed nearly a year ago, at a meeting for smallpox researchers at the World Health Organization. But when Evans tried to publish his research, the journal Nature rejected it, and Science discouraged him from submitting a manuscript for evaluation. An editor at Science told Evans that his work wasn’t novel enough to justify the potential risk of publishing such a double-edged study, the Science article reports.

Evans says that the technology and know-how needed to bring back these types of viruses was already out in the world. “Have I increased the risk by showing how to do this? I don’t know,” Evans told Science. “Maybe yes. But the reality is that the risk was always there.” Now, he says, the question should be how to deal with it. He’s in the process of submitting his research to another journal for publication, he told Science.

Scientists are forbidden from attempting to build the full smallpox genome, or make live smallpox virus in the lab, per WHO guidelines. But Evans’ research reveals that it’s possible to buy the necessary genetic building blocks without raising red flags. And, with enough expertise, it would be reasonably easy for someone to re-create his work. “Maybe not some guy in a cave,” Peter Jahrling, a virologist at the National Institutes of Allergy and Infectious Diseases, told The Washington Post, “but a reasonably equipped undergraduate microbiology lab could repeat this trick.”

But that’s not really something to worry about, Anthony Fauci, the director of the National Institutes of Allergy and Infectious Disease, told TheWashington Post. There are plenty of deadly viruses that are cropping up naturally, and the dangers they pose “are much more of a threat to civilization than the possibility that someone might be able to synthesize a microbe,” he said.

In the meantime, should Evans be allowed to publish his work? Absolutely, Jahrling told Science. It’s novel, it’s important, and, at this point, he says, “The genie is out of the lamp.”